174 THE BUTTERFLIES OF THE BRITISH ISLES. 



(Proc. S. Lond. Ent. and Nat. Hist. Soc. for 1896), in which he 

 gives a most interesting account of the earlier stages of the 

 second brood of this species. 



At the time when the butterflies of the second brood are on 

 the wing, the flower-buds of the ivy (Hedera helix) are still 

 young, and form compact heads. The butterfly, having selected 

 one of these heads, settles upon its top, closes her wings over 

 her back, and bending her abdomen down and round under- 

 neath the buds, affixes an egg to the under side of one of the 

 slender single bud-stalks. In about a week the eggs hatch. 

 The young larva which in colour matches the buds very closely, 

 rests on the bud-stalk Vith its anterior segments, which com - 

 pletely cover its head, pressed closely against the bud, and looks 

 so exactly like a slight swelling of the upper part of the stalk 

 as to make detection a matter of great difficulty, even with the 

 aid of a fairly powerful lens. The larva is very sluggish in its 

 habits, seldom leaving the head of the buds on which it is 

 hatched, so long as sufficient food remains for its nourishment, 

 or occasionally when about to change its skin. It appears to 

 feed only at night, and its manner of feeding, which is the same 

 throughout its life, is to eat a round hole through the outer shell 

 of a bud, and pressing its head forward through it to clear out 

 the soft inside of the bud. In from four to six weeks it is full- 

 fed ; it then quits the buds, and attaches itself by slender threads 

 to a leaf, and in a few days becomes a pupa, in which state it 

 passes the winter. 



Normally the eggs of the spring butterflies are laid on the 

 under side of the calyces of flower-buds of holly {Ilex). The 

 caterpillars feed on the flower-buds and also on the young 

 green berries. They are full grown in about a month, change 

 to chrysalids, and the butterflies emerge in July and August. 

 Among other pabula that have been mentioned are the flowers 

 of dogwood (Cornus sanguinea), berry-bearing alder {Rhamnus 

 frangula), and spindle {Euonymus europaus). 



